Quarterly report pursuant to Section 13 or 15(d)

Common Stock - Stock Options - Additional Information (Detail)

v3.10.0.1
Common Stock - Stock Options - Additional Information (Detail) - USD ($)
3 Months Ended 9 Months Ended
Sep. 30, 2018
Sep. 30, 2017
Sep. 30, 2018
Sep. 30, 2017
Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Common shares reserved for options currently outstanding 665,585   665,585   111,578
Unrecognized compensation expense related to stock options granted $ 2,600,000   $ 2,600,000   $ 2,000,000
Anti-dilutive securities excluded from earning per share computation 3,854,505 174,408 3,854,505 174,408  
Warrant [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Anti-dilutive securities excluded from earning per share computation 3,173,764 174,408 3,173,764 174,408  
Stock Options [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Anti-dilutive securities excluded from earning per share computation 665,585 174,408 665,585 174,408  
Restricted Stock Unit [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Anti-dilutive securities excluded from earning per share computation 15,156 174,408 15,156 174,408  
Stock Options [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Weighted-average period, restricted stock awards     3 years 1 month 6 days    
Stock Options [Member] | Employees and Consultants [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     4 years    
Stock Options [Member] | Minimum [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award expiration period     7 years    
Stock Options [Member] | Minimum [Member] | Board of Directors [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     1 year    
Stock Options [Member] | Maximum [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award expiration period     10 years    
Stock Options [Member] | Maximum [Member] | Board of Directors [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     3 years    
Restricted Stock Unit [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     4 years    
Common shares reserved for awards currently outstanding 15,156   15,156   21,066
Weighted-average period, restricted stock awards     2 years 9 months 18 days    
2018 Equity Incentive Plan [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Common shares reserved for issuance under incentive plan 613,350   613,350    
Award expiration period     10 years    
2018 Equity Incentive Plan [Member] | Minimum [Member] | Employees and Consultants [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     3 years    
2018 Equity Incentive Plan [Member] | Minimum [Member] | Board of Directors [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     1 year    
2018 Equity Incentive Plan [Member] | Maximum [Member] | Employees and Consultants [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     4 years    
2018 Equity Incentive Plan [Member] | Maximum [Member] | Board of Directors [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     3 years    
2018 Equity Incentive Plan [Member] | Stock Options [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Common shares reserved for issuance under incentive plan 1,000,000   1,000,000    
Common shares reserved for options currently outstanding 386,650   386,650    
2017 Equity Incentive Plan [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award expiration period     10 years    
2017 Equity Incentive Plan [Member] | Minimum [Member] | Employees and Consultants [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     3 years    
2017 Equity Incentive Plan [Member] | Minimum [Member] | Board of Directors [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     1 year    
2017 Equity Incentive Plan [Member] | Maximum [Member] | Employees and Consultants [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     4 years    
2017 Equity Incentive Plan [Member] | Maximum [Member] | Board of Directors [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     3 years    
2017 Equity Incentive Plan [Member] | Stock Options [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Common shares reserved for issuance under incentive plan 272,660   272,660    
2010 Performance Incentive Plan [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award expiration period     10 years    
2010 Performance Incentive Plan [Member] | Minimum [Member] | Employees and Consultants [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     3 years    
2010 Performance Incentive Plan [Member] | Minimum [Member] | Board of Directors [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     1 year    
2010 Performance Incentive Plan [Member] | Maximum [Member] | Employees and Consultants [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     4 years    
2010 Performance Incentive Plan [Member] | Maximum [Member] | Board of Directors [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Award vesting period     3 years    
2010 Performance Incentive Plan [Member] | Stock Options [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Common shares reserved for issuance under incentive plan 21,079   21,079    
Common shares reserved for options currently outstanding 5,923   5,923    
2010 Performance Incentive Plan [Member] | Restricted Stock Unit [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Common shares reserved for awards currently outstanding 15,156   15,156